Apparatus for use in washing clam meats



Oct 8, 1957 H. F. sNow APPARATUS FOR USE IN WASHING CLAM MEATS Filed OCT.. l2, 1953 Invezzoa.- Hio 1771522010,

H Hzeg United States O M Y 2,808,612 j s APPARATUS FOR USE IN WASHING CIJ-AM lVlEATS Harold Fi Snow, Pine P oint, Maine,` assigner to The` F. H.

Snow Canning Company, Inc., Pine Point, Maine, a corporation of Maine Application october 12, 1953, sensi No. 385,329 s claims. (c1. 11s-s) This invention relates toapparatus foruse-in ridding the meats of clams and like shellsh of sand.. s

While the invention maybe used to render sand-free such rother shellfish as oysters, quahogs, and all other species of clams, itis discussed-herein withfparticular reference to sea clams and to Vtheir preparation, under commercial. conditions, forV canning and freezing. -Seav sumption and the usual procedure is to subject themfto` a pre-Wash n'Whatis calledan' oyster blower which consists `of an `open-top tank containing water-and having a perforated spreaderv pipe in its bottom by which air is continuously bubbled through the water thereby constantly agitating it to a considerable extent, thus suspending the clam meats in the water and washing them relatively Vfree of sand. The freed sand settles vthrough a perforated false bottom, located above the spreader pipe, and into the bottom of the tank where the Water is relatively quiet. s

Usually, the clam meats are held in suspension inthe oyster blower, during the pre-wash, for periods ranging from two to ve minutes. The clam meats are then removed, Vby sluicing the water containing them, through a port in the side of the tank just aboveits false bottom and onto a perforated tray Where the wash vWater is drained awayleaving the washed drained clam meats ready to be cleaned.

The cleaningV step is a manualoperation involving the removal of the contents of the abdominal cavity. Also during cleaning, certainly loosely attached skin-like mem# branes are torn from the clam meats because of theirV 55 tendency to trapsand particles in their folds.

The cleaned meats are then subjected to a final or finish-washing, using the same equipment employed in fthe pre-wash and in the same manner except that the time the clam meats are held in suspension is usually increased to periods ranging from seven to thirty minutes. After they are again drained, the clam meats are ground or. chopped and then placed into containers for canning or freezing.

The present invention is particularly concerned with the finish-washing step and has for its principal objective the elimination of two major disadvantages inherent in the conventional finish-washing step just described. One of these is that` suflcient sand remains in the product after that step to cause a considerable amount of consumer complaints. The other has to do with the loss of avor through leaching of albuminous matter and solubles pended during washing.

2,808,612 Patented Oct. Y8,- 1957 Careful examination of a considerable number of clam meats washed by the conventional finish-wash technique, above described, would reveal the presence of sand particles in several general locations. Clams, like other marine bi-Valves, take in and discharge large quantities of water -in that part variously known as the head, neck, or Siphon, as their means of obtaining food. Sand may thus be usually found in the siphon area when the clam meat is removed from its shell. During dredging, however, much sand is forced into the shell of the clam and ruptures membranes which normally protect theclam meat from sand particles and prevent the body fluids from mixing with sea water. Some of this sand is also often forced into the meat itself. Examination ofthe muscles, `which control the opening and closing of the shells, shows the presence of an occasionalsand particle firmly entrenched between sections thereof.v Sand is likewise found trapped between a muscle and the tissue which adheres to Vone of its sides. While some of .the loosely held tissue or memb'ranes associated with the clam is removed during the .cleaning operation, thatwhich remainsI often -has sand particles entrapped in its folds.

These places are illustrative of those where sand particles may be firmly lodged in clam meats. In addition, there is an occasional clam whose main jacketing membraneV traps a large amount of sand,` often equalto the weight of the clainitself, andfrequently this membrane holds muchtof the sandduringthepre-wash step, and Whenftha't clam is cleaned, some of thi-sl sand spreads through the mass of ,meats, sometimes finding its way intofcleaned abdominal cavities. Y

be washed for perhaps a half a-rninute inthe so-called oyster blowervtype, of washer for the purpose of washing` away small bits of paunch which are inevitably mingled liquid body, suspending vthe meats in the body by agitation" tofree them of sand and to permit the .freed sand to settlerfrom-the suspension, andthen delivering'the meats to a draining station. Best .results are obtained, as far as sand removal isconcerned, when the meats are `ground and are fed continuously through the body to the drainingtstation. Protection against leaching is effected, in any of the washes, by delivery of the drainage from-the drain-v ing stationback to the liquid body. w

Apparatus for carrying vout the methods, as abovebroadly summarized, .consistssof a `tank having a screen# ing memberV dividing it into an upper part for the meatsv tanda lower part to receive sand freed fromthem -Where leaching is to be avoided, the drainer which receives 'meats in suspension from kthe tank is provided with pump con# trolled means to deliver drainage back to the tank "and the delivery line is usually refrigerated. Y' v Where most effective sand removalis required, the tank is relatively` long a'nd'narrow so thatia continuous flow of suspended meats: may be delivered to the'drainer under i circumstancesensuring Vthe-freeing therefrom of sand and ,other unwanted particles. As above indicated, b est resultsy are obtained Wherek the meats are ground.

In the accompanying drawings, thereis shown illustative ebdrnet'of the invention from-vvliichtliesev and Ingacc'ordanc'e with theinvention, the clam meats mayV ratus for use in continuouslyfwashing clam like meats;

Fig. 2 is a partly sectiollefI `Sill@lifvy 5; @paw shown in Fig. l; and

Fig. 1.

'As nillustrative of apparanis in va cc :orc la.nce withthe in@A vention, there is shown an open-top tankl which rela:- tively long, narrow, and. shallow and is `divided into upper and lower parts by a screening member The upper part is for the clam meats and at one end of the andabove the member 11, there is an outlet12l establishing the level of liquid in the tank v1 0. The apeturesof the Sereesina memberll. are dimeasieaed te prevent the less ef aay appreciable. aaieuatef thepfedief dewtlwaadly therethrough while permitting freed sand particles to settle to the bottom of the lower part/of the tank 19. from they may eeeape through 'die draid 1,3 when the'valye .l is opened.

From the tank 1l), the clam meats are delivered to a drainage station shownas consisting of a vibrating screen 1S located above a drain or collector 16 and vdischagiil'g the drained clam meats onto a tray 17 as indi means for conveying them for a subsequent oper The outlet 12 is shown, for convenience, as discharging directly to the drainage station but, in practice',` tha t i on may be located remote from the tankltl in wh h case the outlet 12 may be a pump controled conduit. A conduit 18, provided with a pump 19, effects communication between the drain 16 and the other'kor infd end of the tank 10. The conduit 18 passes through a refrigerating unit generally indicated at 20 and is provided'a" branch conduit21 having a valve 22. Adjacent thein-, feed end of the tank 1 0 the conduit `18 has a',' l" 2f2 a to,V

which is connected -a fresh water supply line 2 4. dja# cent the T 23 the conduits 18 and 24 are provided with.

valves 25 and 26 respectively. A supply conduit'Z for the .clam meats is shown as entering the the screening member 11.

Liquid and clam meats are thus vintroduced into the upper part of the tank at one end thereof tofestfahlisha stream through it to the draining station. iii 'the tank 10, the vclam meats are so agitated asto feiecf suspension in .the liquid. A s illustrative of agittiiig means, there is shown a perforated pipe 28 .ext dlllgsllb. sfamiany from enero-end ef the tank 1 0 "ujaeeaf the bottom of the lower part thereof. The pipe 28 is`Qc0'1-.

n eeted to a suitable source of air underpressur q not shown, and air 'bubbling up through the liquidfiisnoperative tosuitably agitato the liquid and, additionalljlto keep the apertures of the screening member 11 :o n.U

`To Vfurther illustrate suitable agitating means,

labove its screening vmember v1 1 and supporte'dfby vthe tank end walls for rotation by anylsuitablerneans. The shaft 29 carries a pair of oppositely disposed blades,

each extending approximately the length of thetank'l.

but tapering towards each other as at-31 adjacent the outfeed end thereof.

vThe use of air, for agitatingpnrposes, has the drawback that it is attended by foaming of the liquid, sometimes to an objectionable extent. Forthatrasonfthe conduit 18 is provided with a branch conduit 32 in which there is a pump 33 and which is connected t'o a header 3.4 extending approximately from end-to-end of the tank 10-.at oneA side thereof. Theheader 34 has a plurality of branches 3S extending through that ,sideof the.tank.10 and terminating as .jets .to assist in theagitation -of the Wise 919s f .the :apertures inlthe ...Sereenigagaenihersayfeneerleembiaadea Fig. 3 is a section along' the indicated li 1 1 e s of' the equivalent thereof may be employed to agitate the liquid in the tank 10 to effect the suspension ofthe'clam' meats therein. For reasons that will subsequently be apparent, it is preferred that the agitation of the liquid be decreased-adjacent the outlet 12. This is accomplished by means of the tapered end portion 31 of the blades 30 and may also be elected as. by. the spacing of the holes in the. Spreader Pipe 2.8. and by the. Spacing df the iets 3.5.

relativfo'the outlet' 12;

In. the practise. et the investies, the use. .0f the above. described "apparatus will first b e discussed with reference to the finish-washing of ground clams'. Eor example, clams, after being @lea-ned, may be ground in a grinder having to 2% inch'holes and with clam meats so ground, the apertures in the screening member 11 may be in the order of 3A@ of an inch in diameter.

Such ground clam meats and liquid are continuously delivered iafe the upper Part el? the taak 1.9 at the iafeed and thereof in desired. proiettata- Fer sentiments, the properties beiweed the'el'am meats .add the liqid'is appreXimafelY in. tlle. raage. ef .diie :fait .by 'Weight f alam meats .te fwerada by 'Weialit'dfliqdid te eee' Partliy Weight ef slam .ideate te The .fate e'f delivery et felatn meats' and' liquids iS dictated by the Volume ef .the .taak lll erlie/"e".theieefleennsirgend bern ha the jeugd of washing timeY desired.-

While .in the taak lll, the. .alam meats" are maintained Suspended in the liq'uid by .ag'tatien by "any Suitable meads er .eeaibiaatieiis'tliereef and .the Suspenden dei?? thr'eagh the edtlet 12de .the .vibrating aereea 15 .at a rale Y einlalf.0 .the iat'iut- Drained ideata.' are thuseentialleusly feadied fer' preeessing ii1`yarieji-s'cenyeritional I naniiei'sl` fahkll) add fregi .a .Paeteal standpoint, itis usually.

ventv souring. Thenecessityto'r fso" doing i's dependent i on many factors', such as the "o f the systemjthe'rate the liquid may be chilled to 52 F. or frozen and held fjor' of ow; and the temperature pf the meats and liquids. Typically,ddiiaejeperatien df the system,the"liduid is cooled to approximately 50. F.' At .the en d of arno,

asub's'equent `run thusl Y-toeliniinate the need of starting the system with water which would result in .the delivtained iti aeehyeatienal .finish-.Wash efiifteeii 'miillltesf using mig'mtmd alam meats. This is dem; pagtftd'the shown a shaft 29 extending from end-tofend ofthe ank.

faet that thegrinding .of the .elammeats greatly inetea'ses the eXpoSUre'-i.. ticles lodge. l Another reason for this vhighly ladvantageous result e is the fact that a lesser degree of VI,turbulence is required particles into the bottoni to eiect the suspension offground clam meats than is necessary `in Athejcase `of whole clam meatspthus es 'tablisliing eenditiens faeiliiating .the Settling 0f freed Sand ofthe tank 10 whereth'e liquid is relatively quiet. v

In addition to 's and, otherunwanted particles are often present vin clam meats. For examplejduring 'the' shucki ing step, pieces ofshell from an occasionalV clam'which has been broken duringharvesting 'or in transportation to the cannery, fin-d .their way into the rrieatslY Sometimes asea clam is found with one or more smallipebbles lodged in its Siphon and whilelsome of these pebbles fall out` during the' various steps ofshucking, oftenlthese remain luntilfthe clam meats' are ground which stepj'in the 'SdalPfeeeduidftalefPlaee after the elamme'afs are vffaslied.` r"Llnfortuiiately', bothlth'ef bits Lof "shell and u'"pbb1es','"whien"are usually 'lign spieren; enemiesdie parte by Weight di Rapid.. The preferred precedida 11e. atiareaimately 011e 'Palit'by weight ef .elem meats te .thiee parte by yyeishfe liquidi' cape detection, even if they are loose in the clam meat mass, during the various steps partly because they match so closely the coloring of the meats with which they are intermingled. With `the degree of turbulence required to maintain whole clam rneatsin suspension, all the shell pieces and all the pebbles that may haveA become dislodged, do not settle ltherefrom. When entire tank contents, as in the caseof conventional finish-washing, are discharged onto the draining screen, these unwanted particles often escape detection and are 'swept along with .the product.

In accordance with the invention, pebbles in the siphons are etfectively dislodged by grinding the clam meats prior tothe nish-wash. Because of the lesser turbulence required in accordance-with the invention and because the clam suspension is drawn away continuously from a point near `the surface of the liquid and at a rate perhaps only Vone-tenth that of the conventional procedure, not only 'do these unwanted particles readily settle from the suspension but also the so-called hinges, which have a density more nearly that of the meats than the shell, may be settled from or prevented from -re-entering the suspension by limiting the agitation adjacent the outlet i2 to the minimum required for the satisfactory suspension of the meats in this zone.

The other major advantage of a huish-wash in accordance with the invention is that it avoids the leaching of desirable albuminous matter and solubles from the meats with their consequent undesirable loss being evi- 'denced most plainly by the loss in flavor of the final` product. Leaching, objectionable when washing Whole clams, is potentially more serious in the case of ground clam meats but is avoided in accordance with the invention by utilizing, as the washing medium, the liquid which is continuously removed at the draining station from the clam meat suspension.

When the system is first started, it is lirst filled with water and the proper amount of clam meats. Agitation and circulation are then begun. The liquid portion of the suspension not occluded by the drained, washed clam meats is continuously returned to the intake end of the tank and water is added only to maintain a constant level in the .tank lt). Although, at the start, leaching occurs, it rapidly diminishes as the process is continued until a condition of equilibrium results in which that which is leached equals that absorbed. When such equilibrium is realized, the system can be run indefinitely without any change in respect to the concentration of solubles in the washing liquid or in davor levels of the clam meats. The addition of fresh water is dependent -on the amount of draining to which the meats are subjected, for any increase in their water content represents loss of liquid from the system. As has been noted, at the end of a run, the liquid may be drained off through the branch conduit 2li.l and held for use in filling the tank it) when another run is to be made.

Alternatively, the washing liquid may be .tapped off through the branch conduit 21 at a uniform rate for use in the formulation of such products as clam juice. While the clam meats lose certain amount of the leachable materials originally associated therewith, equilibrium conditions are realized after a short time of operation such that the tapped-off liquid is acceptable for clam juice and the davor of the clam meat is satisfactory.

In conventional finish-Washing, plasmoptysis or swel'- ing of the clam meats occurs concurrently with leaching. in accordance with the invention, this is avoided by the recirculation of the liquid, so that the maintenance of the proper solids content in the drained meats is never a problem.

While the continuous washing of ground clam meats with the liquid being continuously re-cycled, represents preferred treatments, whole clams may be thus processed. In that event, leaching problems are completely avoided but sand removal is not as efective.

It is y'also possible to wash ground cla'm meats either in batches or continuously and discard the liquid. Eifective sand removal results but the leaching problems remain.

Alternatively, batches of whole or ground clam meats may be washed in liquid drained from prior batches and returned to the tank. While the leaching problem is thus overcome, many advantages of the continuous washing process are not realized.

In the finish-washing of clam meats in accordance with the invention, the two principal shortcomings of the conventional finish-wash are surmounted. In addition to more complete sand removal and protection against loss through leaching, otherV advantages are realized such as the more effective removal of shell pieces, pebbles and hinges, material labor'savings, reduced sewerage -disposal problems which are otherwise present because of the high biological oxygen demand ofthe leachable materials, and markedly reduced water consumption.

What I therefore claim and desire to secure by Letters Patent is:

l. Apparatus for washingcomminuted clam meats, comprising a container, said container having a substantially horizontal screen therein dividing it into upper and lower portions, conduit means connected to said container at a point above said screen, a separator operatively associated with said conduit means adjacent said container, a liquid collector below said separator, a conduit interconnecting said collector and said container, and agitating means in said tank operative to effect the suspension of the meats in the liquid in said upper portion.

2. Apparatus for washing comminuted clam meats, comprising an elongated container, said container having a substantially horizontal screen therein dividing it into upper and lower portions, means to circulate liquids through said portions to provide a stream to convey said meats lengthwise through said upper portion, said means including a conduit connected to the down stream end of said container at a point above said screen, a separator operatively associated with said conduit, to separate meats from fluids passing therethrough, uid collecting and returning means in communication with said container adjacent the other end thereof and disposed to receive yfluids from said separator, and agitating means in said tank operative to effect the suspension of said meats as they are being conveyed by said stream through the upper container portion.

3. Apparatus for washing comminuted clam meats, comprising an elongated'container, said container having a substantially horizontal screen therein dividing it into upper and lower portions, means to circulate fluids through said portions to provide a stream to convey meats through said upper portion, said means including a conduit connected to the down stream end of said container at a point above said screen, a separator operatively associated with` said conduit to separate meats from fluids passing therethrough, fluid collecting and returning means in communication with said container adjacent the other end thereof and disposed to receive fluids from said separator, and agitating means in said tank operative to effect the suspension of said meats as they are -being conveyed by said stream through the upper container portion and to.

urge them transversely `of said stream.

4. Apparatus for Washing comminuted clam meats,. comprising an elongated container, said container having; a substantially horizontal screen therein dividing it into. upper and lower portions, means to circulate uids throughE said portions to provide a stream to convey meats through. said upper portion, said means including a conduit connected to the down stream end of said container at a point; above said screen, a separator operatively associated with-V said conduit to separate meats from uids passing there-. through, Yand fluid collecting and returning means in communication with said container adjacent the other endi thereof and disposed to receive uids from said separator,

and agitating means in said tank operative to effect the sus-- pension of,said,meats as they' are beingconveyedby said stream through the upper container portion, said agitatirig meansl including a rotatable memher'disposedin said upper portion with its axis lengthwise of said container andY provided with angularly spaced lblades operative to urge the meats transversely of said stream whereby said stream 'and said rotatable member cooperate to provide for the approximately helical travel of said meats.'

5. Apparatus for Washing com'minuted clam meats, comprising an elongated container, saidcontainer having a substantially horizontal screen therein dividing it into upper and lower portions, means to circulate uids through saidportions to provide aV stream to convey meats through said upper portion, said meansincluding a conduit connectedto the downstream en'd of said container at a point above said screen, a separator operatively associatedwith said conduit to separate meats from fluids passing therethrough, and iluidcollecting and returning means in com,- munication with said container adjacent the other end strear'nthrougli the u'ppe'reontain'er portion and to coast with" said stream to'effect the approximately helical travel ofsid' meats" while in' said upper portion.

References Cited in the tile of this patent UNITEDV STATES PATENTS 1,011,378 Shaffer Dec. 12, 1911 2,Q47,6|8 Jenkins July 14, 1936 27,102,945I I Doxsee et al. Dec. 21, 1937 2,608,715 Harris Sept. 2, 1952 21,640,223,` Secor June 2, 1953 2,652,583A Harris sept. 22, 1953 FOREIGN PATENTS 128,847 Great Britain July `3, 1919 

